Method of manipulating polygonal cross-section cast copper bars

ABSTRACT

The method utilizes a stationary tipping trough including a pair of longitudinally spaced substantially angular supporting surfaces each having a downwardly and inwardly sloping inlet side and an upwardly and outwardly sloping steeper outlet side. A pair of tipping levers are oscillatable by an associated fluid pressure actuator to engage a longitudinal corner edge of a bar in the tipping trough to tilt the bar so that it rests on a different side. A pair of lifters, having projecting fingers, are oscillatable about the same axis as the tilting levers by a different fluid pressure actuator so that the fingers engage the then lower side of a bar in the tipping trough and move the bar over the outlet sides of the supporting surfaces. The tipping trough preferably is arranged between a bar feeding roller conveyor and a bar discharge roller conveyor, and switch means are provided for engagement with a bar moving along the feeding conveyor. The bars have sloping or tapered ends providing respective projecting noses, coplanar with one bar side surface, and the switch means are so arranged that, depending upon which switch is engaged by a projecting nose, an appropriate bar tipping operation is initiated. Alternatively, the switch means may be arranged beneath a bar support surface, again for cooperation with the nose of a bar, or may be arranged to project into the tilting trough for engagement by the nose of a bar.

United States Patent Kreuz et a1.

[451 Dec. 10, 1974 1 1 METHOD OF MANIPULATING POLYGONAL CROSS-SECTIONCAST COPPER BARS Inventors: Otto Kreuz, Duisburg; Stefan Raab, Essen,both of Germany [73] Assignee: Demag Aktiengesellschaft, Duisberg,

Germany [22] Filed: Dec. 21, 1972 211 App]. No.: 317,234

Related US. Application Data Primary ExaminerFrank E. Werner Attorney,Agent, or FirmMcGlew and Tuttle [57] ABSTRACT The method utilizes astationary tipping trough including a pair of longitudinally spacedsubstantially angular supporting surfaces each having a downwardly andinwardly sloping inlet side and an upwardly and outwardly slopingsteeper outlet side. A pair of tipping levers are oscillatable by anassociated fluid pressure actuator to engage a longitudinal corner edgeof a bar in the tipping trough to tilt the bar so that it rests on adifferent side. A pair of lifters, having projecting fingers, areoscillatable about the same axis as the tilting levers by a differentfluid pressure actuator so that the fingers engage the then lower sideof a bar in the tipping trough and move the bar over the outlet sides ofthe supporting surfaces. The tipping trough preferably is arrangedbetween a bar feeding roller conveyor and a bar discharge rollerconveyor, and switch means are provided for engagement with a bar movingalong the feeding conveyor. The bars have sloping or tapered endsproviding respective projecting noses, coplanar with one bar sidesurface, and the switch means are so arranged that, depending upon whichswitch is engaged by a projecting nose, an appropriate bar tippingoperation is initiated. Alternatively, the switch means may be arrangedbeneath a bar support surface, again for cooperation with the nose of abar, or may be arranged to project into the tilting trough forengagement by the nose of a bar.

4 Claims, 17 Drawing Figures METHOD OF MANIPULATING POLYGONALCROSS-SECTION CAST COPPER BARS This is a division of application Ser.No. 152,867 filed June 14, 1971, now US. Pat. No. 3,759,401. issuedSept. 18, 1973.

FIELD OF THE INVENTION This invention relates to a method ofmanipulating polygonal cross-section bars and, more particularly, to amanipulating method which is capable of tilting bars for inspection ofall surfaces thereof in an efficient and expeditious manner.

BACKGROUND OF THE PRIOR ART Manipulators for oblong workpieces having apolygonal cross-section are known both in rolling mill construction andin testing apparatus for castings in foundries. A manipulator used inrolling mill construction consists of a roller bed with rows ofjuxtaposed rollers spaced at substantial center-to-center distances fromeach other and, between these rollers. there are arranged additionalrows of rollers spaced at one-half the center-to-center spacing of thefirst mentioned rollers.

As a result. and as viewed in the axial direction of the rollers.tipping troughs are formed, with two rollers, in tandem relation witheach other, forming a tipping trough. The rollers are driven and pullthe polygonal cross-section workpieces into the trough which tips, dueto gravity, into the surface pointing in the direction of workpiecemovement. The supporting roller. in this position, is also driven, andmoves the workpiece from the trough into the following trough formed bya succeeding roller. The material to be tilted thus is placedsuccessively on all canting surfaces in successive tipping troughs, andthus can be checked by visual inspection. However, this requires anarrangement of several rollers, which in turn results in a relativelylong roller bed and thus a very long manipulator. The known devicetherefore is suitable only in cases where a conveying track is to beconnected with the manipulator.

In another known manipulator, a spoke wheel is provided to receive aworkpiece between adjacent spokes. Rotation of the wheel effects atilting of the workpiece through 180, so that each workpiece can beturned over only on the face opposite the preceding bearing surface orface. The turnover remains limited to the initial position. In addition.this device has the disadvantage that it is very long, and tilting theworkpiece over, in any position, is not possible. Arriving workpiecescan be turned over when they have a predetermined position. but aselected number of tilting operations cannot be effected.

SUMMARY OF THE INVENTION The object of the present invention is toimprove known bar manipulating methods. An improvement meeting allprerequisites requires use of a compact device which permits turning thepolygonal cross-section bar onto all of its sides in succession. orturning with relation to any selected side surface. For stacking copperbars, it is advantageous to place the widest surface of the trapezoidalcross-section on the bottom and, for inspecting the surfaces of bar inrolling mills, it is advantageous to bring all the possible bearingsurfaces successively into the range of view of an inspector.

In accordance with the invention. there is provided a method forcontrolling the turnover operation of polygonal cross-section bars. Themethod is particularly suitable for copper bars which have been producedin a metal mold and which are air-cooled on one surface and have acorrespondingly wide base or bearing surface. These wide base surfacesserve to stack a large number of bars, the bars having a generallytrapezoidal cross-section. In the stacked position, the weight isstamped on the top side of each bar.

In accordance with the method of the invention, the bars assume such adesired position that their position, when brought to a halt on afeeding roller conveyor in advance of a manipulator, is first determinedby actuation of a switch by a tapered tip of the bar, and this switchactuation initiates, by means of a signal, a corresponding number ofoscillations of a swinging drive, after which a swinging drive for thelifters is activated.

An object of the invention is to provide an improved method formanipulating polygonal cross-section bars having tapered noses at eachend coplanar with a surface of the bar.

Another object of the invention is to provide such a method whichpermits turning the bar onto all of its sides in succession, or turningthe bar with respect to any one side.

A further object of the invention is to provide such a method whichresults in a substantial reduction of the space required formanipulating cast copper bars.

For an understanding of the principles of the invention, reference ismade to the following description of typical embodiments thereof asillustrated in the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 is a side elevation view of a manipulator for practicing themethod of the invention;

FIG. 2 is a top plan view of the manipulator shown in FIG. 1;

FIG. 3 is a sectional view taken on the line A-A of FIG. 2, in part, andin part an enlarged front elevation view corresponding to FIG. 2;

FIGS. 4, 6, 8 and I0 are elevation views, taken in a viewing directionalong a roller conveyor. illustrating various phases of the switchingprocedures initiated by arriving bars;

FIGS. 5, 7, 9 and II are side elevation views corresponding,respectively. to FIGS. 4, 6, 8 and 10',

FIGS. I2, 13 and I4 are elevation views illustrating another embodimentofa control switch and its method of operation; and

FIGS. 15, I6 and 17 are elevation views illustrating still anotherembodiment of a control switch and its manner of actuation by bars.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The manipulator illustrated inFIG. 1 is representative of an application of the method of theinvention to an inspection station arranged behind or following a copperbar foundry. In itself, the manipulator therefore need not be used onlyin connection with additional conveyor means. but it can also be usedseparately and the bars do not have to consist solely of metal.

Referring to FIGS. 1, 2 and 3, a frame I is supported on legs 2 and 3,and the material to be turned comprises bars 4. By means of partsdescribed hereinafter, a single bar 4 arrives in tipping trough 5, whichconsists of two supporting surfaces 6 and 7 arranged at an angle to eachother. Supporting surface 6, which is the inlet side, is less steep thansupporting surface 7, which is the trough outlet side. The illustratedbar 4 has a trapezoidal cross-section, and thus has four longitudinallyextending corner edges 8. Each bar, in the usual manner, has tapered tipends or noses 40, such as indicated in FIGS. 5, 7 and 9, which arecoplanar with one surface of the bar, such as, for example, the basesurface 41 of the trapezoidal cross-section. These noses, as best seenin FIG. 16, for example, are formed by two tapered surfaces 51, 51, oneof which extends at a small angle to surface 41 and the other of whichextends at a much steeper angle to surface 41.

As best seen in FIG. 2, two supporting surfaces 6 and two supportingsurfaces 7 are arranged along the length of a bar 4. Each supportingsurface 7 extends as an arc and forms, toward the discharge side of thetrough, a bearing surface 9. Supporting surfaces 6 and 7 are so narrowthat they essentially form rails. As a result, there is sufficient roomto provide tilting or canting levers 10 between each pair of supportingsurfaces 6, 7, and tilting levers 10 are secured to a tubular shaft 11.

Lifters 12 are provided and arranged for swinging or oscillationindependently of shaft 11, each lifter 12 comprising projectionsarranged around the periphery or circumference of a respective wheel 13.Wheels 13 can be turned about the same axle 14 which rotatably supportsshaft 11.

Tipping trough 5 is arranged between a feeding roller conveyor 15 and adischarging roller conveyor 16. The rollers 17 of the respectiveconveyors form conveying planes 18, as best seen in FIG. 1, along whichbars 4 can be conveyed in dependence on the direction of motion of thedriven rollers 17. FIG. 2 illustrates the bar feeding device 19 and thebar discharging device 20.

The pair of tilting levers 10 secured on shaft 11 can be actuated by anoscillating drive 21. For this purpose, shaft 11 has secured thereto alever 22 whose free end is articulated, at a joint 23, to the connectingrod of a hydraulically actuated piston-cylinder drive 24. Drive 24 is,in turn, connected with supporting frame 1 through an articulation at ahousing 25.

Movement of a bar 4 in the direction 19 is limited by a stop 26, inwhich there are arranged switches 27, 28 and 29 for actuating theoscillating drive 21, with the method of operation of these switchesbeing explained hereinafter.

Shaft 11 is tubular or hollow and has, at both ends in its interior,bearings 31 by means of which it is rotat- .ably supported on shaft 30.As best seen in FIGS. 2 and 3, shaft 30 carries the spaced wheels 13which are secured to rotate with shaft 30 by keys 32. In correspondancewith the lengths of bars 4, wheels 13 are arranged between bearings 33which are fixedly mounted on supporting frame 1. Outwardly of bearings33, ratchets 350 are fixed to shaft 30 to rotate therewith, andrespective pairs of levers 35 are oscillatably mounted on the hubs ofeach ratchet 35a. The ends of levers 35 support pivot bolts 36, with onepivot bolt mounting a pawl 37 engageable with the associated ratchet35a. The other pivot bolt connects the associated pair of levers to thepiston rod of a piston-cylinder drive 38. The piston cylinder drives, orlinear fluid pressure actuators, 24 and 38 can be controlledindependently of each other. By virtue of their pivotal interconnectionwith the associated levers 35 through bolts 36, drives 38 can bepositioned on either side of the tilting trough. In the illustratedembodiment, the drives 38 are arranged adjacent feed roller conveyor 15.

The rollers 17 of feed roller conveyor 15, which are driven by means ofchains and sprockets, move bars 4 toward stop 26. As illustrated inFIGS. 4 and 5, the workpiece has the form of a copper bar, and suchcopper bars have tapered tips 40, as described hereinbefore. If bar 4therefore rests on its base 41, which is characteristic of a trapezoidalcross-section, nose 40 will actuate switch 29. Switch 29 transmits acontrol pulse to drive 21 so that the latter either does not perform anymovement at all, if bar 4 is in correct position, or performs apredetermined number of tilting or canting movements, for bar 4, forinspection of all four surfaces of bar 4. A canting or tilting movementis always one complete reciprocation of the piston rod of drive 21.

In the phase illustrated in FIGS. 6 and 7, bar 4 rests on its side face42, and its nose 40 consequently actuates switch 28, with switches 27and 29 remaining inactive. Switch 28 is set, for controlling drive 21,in such a way that a single pulse is emitted. Bar 4 is thus tilted torest on its base 41 and is advanced in this position. Further movementof bar 4 is then effected, on the basis of the last pulse supplied todrive 21, by pivot drive 28 oscillating lifters 12 which push bar 4along trough outlet surfaces 7 and bearing surfaces 9 onto dischargeroller conveyors 16. As stated, the last bar tilting pulse initiatesoperation of drive 38 for lifters 12.

In the phase shown in FIGS. 8 and 9, bar 4 rests on its upper or headsurface 43, so that its tip 40 actuates switch 27. This initiates twotilting cycles effected by drive 21, after which there follows theactuation of drive 38 for lifters 12 to discharge the bar from thetilting trough.

The phase shown in FIGS. 10 and 11 is similar to that in FIGS. 6 and 7,so the switch 28 again is actuated by tip 40 of bar 4 which is nowresting on its side face 44. The same tilting and discharge proceduresoccur as described above.

As shown in FIGS. 12, 13 and 14, other switching means may be providedeither to inspect the bar repeatedly, after a determinable number ofpulses for tilting operations, or to discharge it in a selectedorientation. To this end, there is provided at least one lever 45pivoted intermediate its ends on an axle 46 in supporting frame 1. Eachpivot lever 45 has a tip 47 which extends by a certain amount aboveinlet side 6 of trough 5 and inwardly of inlet side 7 of trough 5.Depending on the orientation of a bar 4, having a tip 40, the tip 47 oflever 45 is engaged by the bar.

In FIG. 12, there is no contact between the bar and the lever 45, sothat there is no movement of the lower end 48 of each lever.Consequently, the actuator 49 of switch 50 remains in the rest position.In FIG. 13, bar 4 has its upper or head face 43 toward the upper end oflever 45, so again there is no pivoting of lever 45 due to the bevel 51at the tip 40 of the bar. This bevel is more clearly illustrated in FIG.15.

ln FIG. 14. however, the base 41 of bar 4 faces outlet side 7 of thetrough and. as bar 4 is not bevelled on its base. as is the case for thesurfaces 51 of FIG. 16. pivot lever 45 is turned by a certain amountcorresponding to the projection of the tip 47. Thus. the rear or lowerend of lever 45 operates actuator 49 to actuate switch 50. The pulsesprovided by switch 50 can be transmitted in the same manner as describedto drive 21, drive 38, or both.

H65. l5, l6 and I7 illustrate a further control switch 52 which. insteadof an operating lever 49, has a reciprocable operating pin 53 butotherwise works in a manner similar to the principle illustrated inFIGS. l2, l3 and 14. In FIG. 15, bar 4 rests on its side face 42, andthus does not touch pin 53 with its tip 40 or, respectively. thesurfaces Sl. The same holds true for the phase illustrated in FIG. 16.In FIG. 17, however, bar 4 rests on its base 41, and its tip 40therefore actuates pin 53 to release a pulse which can be transmittedeither to drive 21, to drive 38 or to both. The embodiments illustratedin FIGS. 12 through [7 thus are suitable for the arrangement of switchesof the types 50 and 52, respectively.

Discharge of bars 4 can be effected either by feed roller conveyor 15orby an easily constructed sloping trough, which has not been shown.along which the bars 4 move by gravity. ln connection with feed rollerconveyor 15, it is advisable to provide a sliding mover 54, as shown inFIG. 2, which moves bar 4 transversely of the roller conveyors in therhythm of the operation ofthe manipulator. through the medium ofa linearactuator of the piston-cylinder type 55. Movement of slide 55 can alsobe initiated by switches 50 or 52.

While specific embodiments of the invention have been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

What is claimed is:

l. A method of manipulating polygonal cross-section cast copper barshaving. at their ends, tapered projecting tips flush with a referencebase surface thereof, said method comprising the steps of transporting abar lengthwise to a position adjacent and parallel to a tipping trough;responsive to arrival of the bar at such position, utilizing the leadingprojecting tip of the bar to determine whether the bar. at suchposition, is resting on its reference base; displacing the bar sidewiseinto the tipping trough; and, responsive to a determination that the baris not resting on its reference base, initiating a number of tiltingmovements of the bar, about its corner edges, in the tipping trough,sufficient to cause the bar to rest on its reference base in thetripping trough.

2. A method of manipulating polygonal cross-section cast copper bars, asclaimed in claim I, in which, if the bar is resting on its referencebase at such position, no tilting movements of the bar, in the tippingtrough, are performed.

3. A method of manipulating polygonal cross-section cast copper bars, asclaimed in claim I, including the step of, responsive to completion ofthe number of tilting movements necessary to cause the bar to rest onits reference base in the tipping trough, initiating discharge of thebar from the tipping trough.

4. A method of manipulating polygonal cross-section cast copper bars, asclaimed in claim 1, in whichdetermination of whether or not the bar isresting on its reference base in such position is effected by engagementof the leading tip of the bar with a selected one of three switches whenthe bar, in such position. is not resting on its reference base; andcontrolling the number of resulting tilting movements of the bar in thetipping trough in accordance with the particular switch actuated by theleading tip of the bar.

t I! t

1. A method of manipulating polygonal cross-section cast copper barshaving, at their ends, tapered projecting tips flush with a referencebase surface thereof, said method comprising the steps of transporting abar lengthwise to a position adjacent and parallel to a tipping trough;responsive to arrival of the bar at such position, utilizing the leadingprojecting tip of the bar to determine whether the bar, at suchposition, is resting on its reference base; displacing the bar sidewiseinto the tipping trough; and, responsive to a determination that the baris not resting on its reference base, initiating a number of tiltingmovements of the bar, about its corner edges, in the tipping trough,sufficient to cause the bar to rest on its reference base in thetripping trough.
 2. A method of manipulating polygonal cross-sectioncast copper bars, as claimed in claim 1, in which, if the bar is restingon its reference base at such position, no tilting movements of the bar,in the tipping trough, are performed.
 3. A method of manipulatingpolygonal cross-section cast copper bars, as claimed in claim 1,including the step of, responsive to completion of the number of tiltingmovements necessary to cause the bar to rest on its reference base inthe tipping trough, initiating discharge of the bar from the tippingtrough.
 4. A method of manipulating polygonal cross-section cast copperbars, as claimed in claim 1, in which determination of whether or notthe bar is resting on its reference base in such position is effected byengagement of the leading tip of the bar with a selected one of threeswitches when the bar, in such position, is not resting on its referencebase; and controlling the number of resulting tilting movements of thebar in the tipping trough in accordance with the particular switchactuated by the leading tip of the bar.